com.ibm.og.s3.v4.DecodedStreamBuffer.java Source code

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Here is the source code for com.ibm.og.s3.v4.DecodedStreamBuffer.java

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/*
 * Copyright 2014-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file except
 * in compliance with the License. A copy of the License is located at
 *
 * http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 */
package com.ibm.og.s3.v4;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.amazonaws.AmazonClientException;

class DecodedStreamBuffer {
    private static final Log log = LogFactory.getLog(DecodedStreamBuffer.class);

    private final byte[] bufferArray;
    private final int maxBufferSize;
    private int byteBuffered;
    private int pos = -1;
    private boolean bufferSizeOverflow;

    public DecodedStreamBuffer(final int maxBufferSize) {
        this.bufferArray = new byte[maxBufferSize];
        this.maxBufferSize = maxBufferSize;
    }

    public void buffer(final byte read) {
        this.pos = -1;
        if (this.byteBuffered >= this.maxBufferSize) {
            if (log.isDebugEnabled()) {
                log.debug("Buffer size " + this.maxBufferSize + " has been exceeded and the input stream "
                        + "will not be repeatable. Freeing buffer memory");
            }
            this.bufferSizeOverflow = true;
        } else {
            this.bufferArray[this.byteBuffered++] = read;
        }
    }

    public void buffer(final byte[] src, final int srcPos, final int length) {
        this.pos = -1;
        if (this.byteBuffered + length > this.maxBufferSize) {
            if (log.isDebugEnabled()) {
                log.debug("Buffer size " + this.maxBufferSize + " has been exceeded and the input stream "
                        + "will not be repeatable. Freeing buffer memory");
            }
            this.bufferSizeOverflow = true;
        } else {
            System.arraycopy(src, srcPos, this.bufferArray, this.byteBuffered, length);
            this.byteBuffered += length;
        }
    }

    public boolean hasNext() {
        return (this.pos != -1) && (this.pos < this.byteBuffered);
    }

    public byte next() {
        return this.bufferArray[this.pos++];
    }

    public void startReadBuffer() {
        if (this.bufferSizeOverflow) {
            throw new AmazonClientException("The input stream is not repeatable since the buffer size "
                    + this.maxBufferSize + " has been exceeded.");
        }
        this.pos = 0;
    }
}